The entertainment industry is involved in a continual struggle to keep movies from being illegally copied. Unfortunately, the same technological advances that have made distributing high quality movies easier have made high quality illegal copies easier to produce. Of particular concern is the copying of high-bandwidth digital video content such as DVDs. Various methods have been employed to protect the content of DVDs from being copied illegally. One such method has been to equip DVD players with Macrovision, or a similar copy protection system. Common copy protection systems allow a media player to detect connections to multiple recording devices, and to scramble or otherwise alter the video data so that quality copies cannot be made. Because of the importance of preventing high quality copies from being made, a more secure form of copy protection, known as Content Scrambling System (CSS), was developed. Using CSS, the content of a DVD is encrypted, allowing the content of the DVD to be read only through the use of an encryption key stored on the DVD and a decryption key stored on the DVD player.
The use of encryption to protect DVDs from being illegally copied has been used much more frequently as DVD use has expanded. Many computers are being sold with built-in DVD drives and software players. While the content of the video and audio data in the DVD is encrypted, once the DVD player software has decoded the content, the content is decrypted and unsecured. Video controllers can be made with stored encryption keys that correspond to encryption keys on digital displays, allowing the content between the video controller and the display to be encrypted; however, installing a unique set of encryption keys during the production of the video controller hardware can be expensive. Furthermore, no insurance can be made of the security of data between the system's software and the video controller, within the information handling system.